A stroller becomes necessary equipment for a family that has a baby when the parents need to take the baby to the outdoors, and it is usually designed in a collapsible form to facilitate handling/storing. For instance, U.S. patent publication No. 2003/0201626 A1 has disclosed a collapsible stroller. However, although this type of collapsible strollers are able to collapse in height direction and front/rear direction (depth direction), the size in the width direction of the stroller is not reduced, that is, the width of the stroller remains unchanged after the stroller being collapsed. Therefore, reducing the volume of a collapsed stroller to a maximum degree is not fully achieved.
U.S. Pat. No. 7,178,822 disclosed a stroller frame structure allowing the stroller being collapsed in two different directions. Specifically, this collapsible stroller frame structure can be collapsed in both the front/rear direction (depth direction) and width direction so as to reduce the volume of the collapsed stroller. Although this type of collapsible stroller design allows the width of the stroller to be reduced after being collapsed, it requires two steps and/or two hands of the user to perform the collapsing operation. Therefore, from simplifying the collapsing operation point of view, this type of stroller obviously does not meet the easy-to-use requirement.
Therefore, there exists a need for a collapsible stroller that the collapsing operation can be operated with one hand of a user and the volume of the collapsed stroller can be minimized.